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Abstract:

The invention relates to a catheter introducer comprising: a tube-like
introducer sheath; an introducer hub having a distal section and a
proximal section, wherein the distal section is joined to the proximal
end of the introducer sheath and the proximal section defines a chamber;
a needle extending through the introducer hub and the introducer sheath
and having opposite proximal and distal ends, the distal end forming a
needle tip; a needle hub attached to the proximal end of the needle; a
needle safety device slidably arranged on the needle, wherein the needle
safety device is retained in the chamber of the introducer hub when the
needle extends through the introducer hub and the introducer sheath, and
removable from the introducer hub once the needle tip is received in the
needle safety device upon withdrawal of the needle from the introducer
sheath.

Claims:

1-41. (canceled)

42. A catheter introducer comprising: a tube-like introducer sheath; an
introducer hub having a distal section and a proximal section, wherein
the distal section is joined to the introducer sheath and the proximal
section defines a chamber; a needle extending through the introducer hub
and the introducer sheath and having opposite proximal and distal ends,
wherein the distal end forms a needle tip; a needle hub attached to the
proximal end of the needle; and a needle safety device slidably arranged
on the needle, wherein the needle safety device is retained in the
chamber of the introducer hub when the needle extends through the
introducer hub and the introducer sheath, and removable from the
introducer hub once the needle tip is received in the needle safety
device upon withdrawal of the needle from the introducer sheath, the
needle safety device comprising a base portion and first and second jaws
extending from the base portion in a generally axial direction, wherein
at least the first jaw and the base portion are integrally formed of a
plastic material; and the needle safety device further comprising two
generally L-shaped extensions formed on opposite sides of the needle
safety device for engagement with the introducer hub.

43. A catheter introducer in accordance with claim 42, wherein seen in a
radial direction, a part of the needle safety device is arranged between
the introducer hub and the needle hub.

44. A catheter introducer in accordance with claim 42, wherein the two
generally L-shaped extensions are formed in the region of a proximal end
of the needle safety device.

45. A catheter introducer in accordance with claim 42, wherein each
L-shaped extension has an axial section extending generally in an axial
direction at a distance from a base portion or a reinforced jaw portion
of the needle safety device.

46. A catheter introducer in accordance with claim 45, wherein the
proximal section of the introducer hub is configured to be received
between the axial sections and the base portion or the reinforced jaw
portions of the needle safety device.

47. A catheter introducer in accordance with claim 46, wherein locking
means are provided to hold the proximal section of the introducer hub in
place between the axial sections and the base portion or the reinforced
jaw portions of the needle safety device.

48. A catheter introducer in accordance with claim 47, wherein the
locking means comprise a locking protrusion on the respective one part
and a corresponding locking depression in the respective other part.

49. A catheter introducer in accordance with claim 42, wherein the
proximal section of the introducer hub is formed from two opposite tube
sections extending in an axial direction.

50. A catheter introducer in accordance with claim 42, wherein the needle
hub comprises a main body and two opposite tube sections extending in an
axial direction from a distal end of the main body.

51. A catheter introducer in accordance with claim 42, wherein the
proximal section of the introducer hub is formed from two opposite tube
sections extending in an axial direction and the needle hub comprises a
main body and two opposite tube sections extending in an axial direction
from a distal end of the main body, wherein the tube sections of the
needle hub are configured to engage between the tube sections of the
introducer hub such that the tube sections of the introducer hub and the
tube sections of the needle hub form a substantially closed tube.

52. A catheter introducer in accordance with claim 42, wherein a main
body of the needle hub comprises a tube-like portion configured to
receive both a base portion of the needle safety device and a portion of
the proximal section of the introducer hub.

53. A catheter introducer in accordance with claim 52, wherein locking
means are provided to hold the portion of the proximal section of the
introducer hub in place in the tube-like portion of the needle hub.

54. A catheter introducer in accordance with claim 53, wherein the
locking means comprise a locking protrusion on the respective one part
and a corresponding locking depression in the respective other part.

55. A catheter introducer in accordance with claim 42, wherein the first
jaw is substantially rigid and the second jaw has spring-like properties.

56. A catheter introducer in accordance with claim 55, wherein the second
jaw includes a strip of sheet metal or plastic.

57. A catheter introducer in accordance with claim 42, wherein the first
jaw and the second jaw are integrally formed with the base portion.

58. A catheter introducer in accordance with claim 57, wherein both jaws
have spring-like properties.

59. A catheter introducer in accordance with claim 42, wherein the second
jaw has a distal end section which extends towards the first jaw such
that it sits on the needle when the needle extends through the needle
safety device, thereby deflecting the second jaw outwardly against a
restoring force, and blocks the needle tip from protruding from the
needle safety device when the needle tip is received between the jaws.

60. A catheter introducer in accordance with claim 42, wherein an elastic
element surrounds the first and second jaws in order to positively
collapse the jaws when the needle tip is received between the jaws.

61. A catheter introducer in accordance with claim 42, wherein the needle
extends through an axial bore in the base portion of the needle safety
device, wherein the cross section of the bore is adapted to the main
profile of the needle, and the needle has an enlargement near the needle
tip rendering the outer diameter of the needle, seen in at least one
direction, greater than the diameter of the bore.

62. A needle safety device for guarding the tip of a needle of a catheter
introducer or an intravenous catheter apparatus having an introducer hub,
comprising: a base portion and first and second jaws extending from the
base portion in a generally axial direction, wherein at least the first
jaw and the base portion are integrally formed of a plastic material; and
two generally L-shaped extensions formed on opposite sides of the needle
safety device for engagement with the introducer hub.

Description:

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to India Application No.
1293/DEL/2008, filed May 28, 2008, the disclosure of which is
incorporated herein by reference.

[0002] The present invention relates to a catheter introducer, in
particular an over-the-needle peel-away catheter introducer, comprising a
tube-like introducer sheath; an introducer hub having a distal section
and a proximal section, wherein the distal section is joined to a
proximal end of the introducer sheath and the proximal section defines a
chamber; a needle extending through the introducer hub and the introducer
sheath and having opposite proximal and distal ends, wherein the distal
end forms a needle tip; and a needle hub attached to the proximal end of
the needle.

[0003] As used herein, the term proximal refers to a location on the
device closest to, for example, a clinician using the device. Conversely,
the term distal refers to a location on the device farthest from the
clinician, such as the distal needle tip to be inserted into a patient's
vein.

[0004] A catheter introducer of the above kind is generally known and
typically used to facilitate insertion and placement of a catheter or
another medical device into a patients vasculature. A conventional
peel-away catheter introducer, which is also referred to as a peelable or
splittable or a tear-away catheter introducer comprises a pair of wings
extending transversely from the introducer hub.

[0005] When using the peel-away catheter introducer a clinician grabs the
needle hub along with the introducer hub and inserts the distal portions
of the needle and of the introducer sheath at a selected site into a
patient's skin. The clinician advances the device until venipuncture has
been confirmed, for example, when blood enters a flashback chamber formed
in the needle hub. After venipuncture has been confirmed, the clinician
advances the distal end portion of the introducer sheath into the
patient's vein and withdraws the needle. With the catheter introducer
properly placed, the clinician can then insert a medical device, such as
a catheter, into the proximal opening of the introducer sheath and
advance the medical device through the introducer sheath until it is
properly placed in the patient's vasculature. After placement of the
medical device the clinician withdraws the introducer sheath out of the
venipuncture site. The clinician then splits the introducer hub and
introducer sheath into two respective separate halves by a combination of
twisting and/or pulling apart of the wings along tear lines provided in
the introducer hub and introducer sheath until the two halves of the
introducer hub and introducer sheath split apart. The clinician can thus
remove the introducer hub and introducer sheath while the catheter
inserted into the patient's vein remains in place.

[0006] Due to the increasing incidence of blood born pathogens such as
human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis
C virus (HCV) there is a need to protect clinicians or other medical
professionals or personnel handling catheter introducers from accidental
contact with the sharp needle tip after withdrawal of the needle from the
introducer sheath and introducer hub.

[0007] It is an object of the invention to provide a catheter introducer
which provides reliable protection against accidental pricking by the
needle once the needle has been withdrawn from the introducer sheath and
introducer hub.

[0008] This object is satisfied by a catheter introducer having the
features of claim 1.

[0009] The catheter introducer of the invention comprises a tube-like
introducer sheath; an introducer hub having a distal section and a
proximal section, wherein the distal section is joined to a proximal end
of the introducer sheath and the proximal section defines a chamber; a
needle extending through the introducer hub and the introducer sheath and
having opposite proximal and distal ends, wherein the distal end forms a
needle tip; a needle hub attached to the proximal end of the needle; and
a needle safety device slidably arranged on the needle, wherein the
needle safety device is retained in the chamber of the introducer hub
when the needle extends through the introducer hub and the introducer
sheath and removable from the introducer hub once the needle tip is
received in the needle safety device upon withdrawal of the needle from
the introducer sheath.

[0010] The needle safety device is operative as a guard for the needle tip
by automatically covering the needle tip during withdrawal of the needle
from a patient and subsequently from the introducer sheath. The needle
safety device thereby serves to prevent accidental pricking of, for
example, a clinician by the needle tip after removal of the needle from
the introducer sheath. Hence, the needle can be safely disposed of after
use.

[0011] According to an embodiment, a part of the needle safety device is,
seen in a radial direction, arranged between the introducer hub and the
needle hub. In this way, a not only a safe seat of the needle safety
device in the chamber of the introducer hub but also a secure connection
between the introducer hub and the needle hub are achieved prior to
withdrawal of the needle from the introducer sheath. Furthermore, the
arrangement of a part of the needle safety device between the introducer
hub and the needle hub facilitates a correct positioning of the needle
safety device in the introducer hub and thus makes the assembly and
ultimately the manufacture of the catheter introducer easier and less
expensive.

[0012] According to a further embodiment, the needle safety device
comprises two generally L-shaped extensions formed on opposite sides of
the needle safety device, preferably in the region of a proximal end
thereof. Each L-shaped extension may have an axial section extending
generally in an axial direction at a distance from a base portion or a
reinforced jaw portion of the needle safety device. As used herein, the
axial direction is defined by the longitudinal axis of the introducer
sheath and of the needle extending therethrough.

[0013] Preferably, the proximal section of the introducer hub is
configured to be received between the axial sections and the base portion
or the reinforced jaw portions of the needle safety device.

[0014] According to a further embodiment, the proximal section of the
introducer hub is formed from two opposite proximal tube sections
extending in the axial direction. Similarly, the needle hub may comprise
a main body and two opposite tube sections extending in the axial
direction from a distal end of the main body.

[0015] Preferably, the tube sections of the needle hub are configured to
engage between the proximal tube sections of the introducer hub such that
the tube sections of the needle hub and the proximal tube sections of the
introducer hub together form a substantially closed tube. Because of this
substantially closed tube the chamber defined by the proximal section of
the introducer hub is also substantially closed, such that the needle
safety device received in the chamber is protected from outside
influences. This helps to permanently maintain a reliable functioning of
the needle safety device.

[0016] According to a further embodiment, the main body of the needle hub
comprises a tube-like portion configured to receive both a base portion
of the needle safety device and a portion of the proximal section of the
introducer hub. In the assembled state, i.e. prior to withdrawal of the
needle, the tube-like portion of the main body of the needle hub hence
surrounds a part of the needle safety device as well as a part of the
proximal section of the introducer hub, thereby not only protecting the
needle safety device but also preventing the introducer hub and
consequently the introducer sheath from accidentally splitting in halves.

[0017] According to a further embodiment, locking means are provided to
hold the portion of the proximal section of the introducer hub in place
between the axial sections and the base portion or the reinforced jaw
portions of the needle safety device. The locking means help to secure
the needle safety device at the introducer hub as long as the needle has
not been fully withdrawn from the introducer sheath and the needle tip
has not been received in the needle safety device. Hence, the needle can
move relative to the needle safety device until the needle tip is safely
received in the needle safety device. The locking means thus ensure a
correct functioning of the needle safety device.

[0018] According to a further embodiment, locking means are provided to
hold the proximal section of the introducer hub in place in the tube-like
portion of the needle hub. The locking means ensure a safe connection
between the introducer hub and needle hub and thereby prevent the needle
from being accidentally withdrawn from the introducer sheath.

[0019] Preferably, both the locking means operating between the introducer
hub and the needle safety device and the locking means operating between
the introducer hub and the needle hub comprise a locking protrusion on
the respective one part and a corresponding locking depression in the
respective other part. For instance, respective locking protrusions may
be provided in the region of the proximal ends of the proximal tube
sections of the introducer hub, whereas corresponding grooves may be
provided at the inner side of the tube-like portion of the needle hub and
of the generally L-shaped extensions of the needle safety device.

[0020] The needle safety device may comprise first and second jaws
extending from the base portion in a generally axial direction.

[0021] According to one embodiment, the first jaw is integrally formed
with the base portion and, preferably, substantially rigid. Due to the
first jaw being formed integrally with the base portion, the number of
parts in the needle safety device is reduced and the simplicity thereof
increased. Forming the base portion, and thus preferably also the first
jaw, from a plastic material helps to reduce the costs of manufacturing
the needle safety device. The first jaw being substantially rigid
increases the integrity of the needle safety device. At the same time, a
reliable functioning of the needle safety device can be ensured by a
suitable deflectability of the second jaw.

[0022] The second jaw may include a strip of material having spring-like
properties, for example a strip of sheet metal or a strip of a suitable
plastic material. Because of the first and second jaws being made from
two separate parts, the needle safety device can easily be adapted to
needles of different thicknesses. Furthermore, due to its simple design
the needle safety device and, thus, the entire catheter introducer can be
manufactured at low cost. Due to its spring-like properties the second
jaw may be deflected against a restoring force by the needle extending
all the way through the needle safety device, such that the second jaw
snaps in front of the needle tip as soon as the needle tip is moved
inbetween the two jaws, thereby safely guarding the needle tip.

[0023] According to an alternative embodiment that can also be
manufactured at low cost, the first and second jaws may be formed
integrally with the base portion, wherein preferably both jaws have
spring-like properties.

[0024] The second jaw may have a distal end section which extends towards
the first jaw such that it sits on the needle when the needle extends
through the needle safety device, thereby deflecting the second jaw
outwardly against a restoring force, and blocks the needle tip from
protruding from the needle safety device when the needle tip is received
between the jaws, thereby safely guarding the needle tip in the needle
safety device.

[0025] According to a further embodiment an elastic element, in particular
a tension ring, surrounds the first and second jaws in order to
positively collapse the jaws when the needle tip is received between the
jaws. Preferably, the elastic element and the jaws are configured such
that the second jaw can be spread away from the first jaw against a
restoring force of the elastic element in order to allow the needle to
extend all the way through the needle safety device.

[0026] Due to the elastic element exerting its restoring force on the
second jaw in the deflected state of the second jaw, which is the state
in which the catheter introducer is typically shelved prior to use, the
elastic element ensures that the spread apart jaws will snap together and
guard the needle tip upon withdrawal of the needle from the introducer
sheath even after a longer shelf time, thereby continuously ensuring a
correct functioning of the needle safety device. In addition, the elastic
element prevents the jaws from becoming loose when the needle safety
device slides along the needle, thereby further adding to a correct
functioning of the needle safety device. Furthermore, the elastic element
helps prevent the needle tip from protruding sideways out of the needle
safety device, thereby further increasing the protective function of the
needle safety device.

[0027] According to a further embodiment the needle extends through an
axial bore in the base portion of the needle safety device, wherein the
cross section of the bore is adapted to the main profile of the needle,
and the needle has an enlargement near the needle tip rendering the outer
diameter of the needle, seen in at least one direction, greater than the
diameter of the bore. The enlargement prevents the needle safety device
from sliding off the needle when the needle tip is received between the
jaws, thereby even further improving the protective function of the
needle safety device.

[0028] Further subject matter of the invention is a needle safety device
for guarding the tip of a needle of a medical apparatus, for example, a
catheter introducer of the above described type or an intravenous
catheter apparatus, which comprises a base portion and two jaws extending
therefrom and defining an axial direction and two generally L-shaped
extensions formed on opposite sides of the needle safety device, wherein
each L-shaped extension has an axial section extending generally in the
axial direction at a distance from the base portion or from reinforced
portions of the jaws (claim 20). Apart from that, the needle safety
device may be configured similar to the needle safety device of the above
described catheter introducer.

[0029] Preferred embodiments of the invention are described in the
following description and in the accompanying drawings, wherein:

[0030] FIG. 1a to 1c show (a) a first longitudinal sectional view of a
catheter introducer according to the invention, (b) a second longitudinal
sectional view of the catheter introducer, and (c) an enlargement of a
portion of FIG. 1a;

[0031] FIGS. 2a and 2b show perspective views of an introducer hub of the
catheter introducer of FIG. 1 and of the introducer hub attached to an
introducer sheath;

[0032] FIGS. 3a and 3b show (a) a perspective view of a needle hub of the
catheter introducer of FIG. 1 and (b) a side view of the needle hub
attached to a needle;

[0033] FIGS. 4a to 4f show (a) a perspective view of a needle safety
device of the catheter introducer of FIG. 1, (b) a longitudinal sectional
view of the needle safety device, (c) a side view of the needle safety
device, (d) a plan view of the needle safety device, (e) a side view of
the needle safety device guarding the tip of a needle, and (f) a
longitudinal sectional view of the needle safety device guarding the
needle tip; and

[0034] FIGS. 5a to 5f show (a) a perspective view, (b) a side view, (c) a
longitudinal sectional view, and (d) a plan view of an alternative needle
safety device for the catheter introducer of FIG. 1, and (e) a side view
and (f) a longitudinal sectional view of the needle safety device
guarding the tip of a needle.

[0035] FIGS. 1a and 1b show longitudinal sectional views of an
over-the-needle peel-away catheter introducer of the invention. The
catheter introducer comprises a tube-like introducer sheath 10 having a
proximal end region 12 that is joined to an introducer hub 14.

[0036] Furthermore, the catheter introducer comprises a needle 16 having a
distal end that forms a needle tip 18 and a proximal end that is attached
to a needle hub 20.

[0037] Prior to use of the catheter introducer, the needle hub 20 is
connected to the introducer hub 14 such that the needle 16 extends all
the way through the introducer hub 14 and the introducer sheath 10 and
the needle tip 18 protrudes beyond a distal end of the introducer sheath
10.

[0038] In order to prevent accidental pricking by the needle tip 18 prior
to use of the catheter introducer, an elongate cap 22 or protective tube
is mounted to the introducer hub 14, which covers the length of the
introducer sheath 10 and also the needle tip 18 protruding therefrom.

[0039] As can be taken in more detail from FIG. 2, the introducer hub 14
includes a distal section 24 and a proximal section 26. The distal
section 24 has smaller inner and outer diameters than the proximal
section 26 and is joined to the proximal end region 12 of the introducer
sheath 10.

[0040] In the transition region between the distal section 24 and the
proximal section 26 a funnel-like structure 28 is formed in the
introducer hub 14, which helps to facilitate the introducing of a medical
device, for example a catheter, into the introducer sheath 10 after the
introducer sheath 10 has been inserted into the vein of a patient.
Furthermore, two wings 30 extend transversely from the introducer hub 14
in the transition region between the distal section 24 and the proximal
section 26.

[0041] Both the distal section 24 and the proximal section 26 of the
introducer hub 14 are formed from pairs of opposite axially extending
tube sections 32, 34 which define first and second halves of the
introducer hub 14. Prior to use, the first and second halves of the
introducer hub 14 are connected to each other by the funnel-like
structure 28.

[0042] Once a medical device, such as a catheter, has been introduced
through the introducer sheath 10 into a patient's vein, the person
handling the catheter introducer, for example a clinician, withdraws the
introducer sheath 10 from the venipuncture site. By a combination of
twisting and/or pulling apart of the wings 30 the clinician then splits
the introducer hub 14 into its two separate halves, thereby also tearing
the introducer sheath 10, such that the introducer hub 14 and the
introducer sheath 10 can be removed from the catheter. In order to
facilitate the breaking of the introducer hub 14 into its two halves,
tear lines 36 may be provided in the funnel-like structure 28 and also in
the introducer sheath 10.

[0043] As can be seen in FIG. 3, the needle hub 16 comprises a main body
38 and two opposite tube sections 40 which extend in an axial direction
from a distal end of the main body 38. The tube sections 40 of the needle
hub 20 are configured to engage between the proximal tube sections 34 of
the introducer hub 14 such that the proximal tube sections 34 of the
introducer hub 14 and the tube sections 40 of the needle hub 20 form a
substantially closed tube.

[0044] To this end, the tube sections 40 of the needle hub 20 and the
proximal tube sections 34 of the introducer hub 14 have substantially the
same length and curvature, and the tube sections 40 of the needle hub 20
have a width corresponding to the gap between the proximal tube sections
34 of the introducer hub 14.

[0045] Referring again to FIGS. 1a and 1b, the proximal tube sections 34
of the introducer hub 14 and the tube sections 40 of the needle hub 20
together form a chamber 42 for a needle safety device 44 which is
slidably arranged on the needle 16.

[0046] As shown in FIG. 4, the needle safety device 44 comprises a main
part 46, a clip 48 and a tension ring 50.

[0047] The main part 46 is made from a plastic material and comprises a
base portion 52 and an elongate portion 54 forming a first jaw 55. The
base portion 52 is of substantially cylindrical shape and has a bore 56
extending therethrough in the axial direction for receiving the needle
16.

[0048] The elongate portion 54 is of semi-cylindrical shape and extends
from the base portion 52 in the axial direction. The elongate portion 52
has a groove 58 formed in its flat side 60, which extends in the axial
direction along the entire length of the elongate portion 54 and forms an
extension of the bore 56 in the base portion 52. While the bore 56 has a
generally circular cross section that is adapted to the main outer
profile of the needle 16, the groove 58 has a generally semi-circular
cross section.

[0049] The clip 48 is formed from a strip of sheet metal having
spring-like properties, such a steel or the like. Alternatively, the clip
48 could be formed from a plastic material which has suitable spring-like
properties.

[0050] The clip 48 forms a second jaw 62 and comprises a base section 64
and a deflectable section 66. The base section 64 includes an axial
section part 68 and a radial section part 70. It is adapted to engage
with the base portion 52 of the main part 46 such that the axial section
part 68 lies against the outer surface of the base portion 52 while the
radial section part 70 lies against a rear or proximal end face of the
base portion 52, when the clip 48 is attached to the main part 46. In
order to ensure a correct positioning of the main part 46 and the clip
48, the base portion 52 is provided with a guide 74 for the clip 48.

[0051] The clip 48 is secured to the main part 46 by means of a heat
sealing connection. To this end, the main part 46 initially has a pillar
or pin 76 formed at its proximal end face and extending generally in the
axial direction. The clip 48 has a corresponding opening 78 formed in its
radial section part 70 for receiving the pillar or pin 76 when the clip
48 is mounted on the main part 46. Once the clip 48 has been brought into
its correct position relative to the main part 46 the pillar or pin 76
extending through the opening 78 of the clip 48 is deformed by heat
and/or pressure in order to increase the diameter of the pillar or pin
76. By making the diameter of the pillar or pin 76 larger than the
diameter of the opening 78, the clip 48 is safely fixed at the main part
46. Alternatively, the clip 48 could be secured to the main part 46 by
means of gluing or welding or any other suitable type of connection.

[0052] The base section 64 of the clip 48 passes into the deflectable
section 66 via a step-like bending of the sheet metal strip. The
deflectable section 66 includes a straight section part 80 which is
reinforced by two elongate wings 82 that extend on either side of the
straight section part 80 and are bent inwards, i.e. towards the elongate
portion 54, by an angle of substantially 90°. In a relaxed state
of the clip 48 mounted on the main part 46 (FIGS. 4b and 4c), the
straight section part 80 does not exactly extend in the axial direction,
but is bent slightly towards the elongate portion 54 of the main part 46.

[0053] In the region of its distal end, the straight section part 80
passes into a head section part 84 which extends beyond the free end of
the elongate portion 54 of the main part 46. The head section part 84 has
a generally V-like shape with the peak of the V pointing in the axial
direction and the free leg 86 of the V extending towards the elongate
portion 54.

[0054] The tension ring 50 surrounds the elongate portion 54 of the main
part 46 and the straight section part 80 of the clip 48 in the region of
the elongate wings 82. The tension ring 50 is made from a material having
elastic properties, for example rubber. The tension ring 50 is configured
so that the deflectable section 66 of the clip 48 is deflected against a
restoring force of the tension ring 50, when the needle 16 extends all
the way through the needle safety device 44. This situation is called the
deflected state of the needle safety device 44 and is shown in FIG. 1b.

[0055] When the needle 16 does not extend all the way through the needle
safety device 44 (FIGS. 4e and 4f) or when there is no needle 16 at all
(FIGS. 4b and 4c), the deflectable section 66 of the clip 48 is drawn
towards the elongate portion 54 of the main part 46 by the tension ring
50. In this situation, which is referred to as the collapsed state of the
needle safety device 44, the head section part 84 of the clip 48 overlaps
with or extends over at least a portion of the distal end face 90 of the
elongate portion 54, thereby preventing the needle tip 18 from protruding
out of the needle safety device 44 at the distal end thereof.

[0056] As has been mentioned above, the bore 56 provided in the base
portion 52 of the main part 46 of the needle safety device 44 is adapted
to the main outer profile of the needle 16. As is indicated in FIG. 3b,
the needle 16 is provided with an enlargement 92 near the needle tip 18,
which renders the outer diameter of the needle 16, seen in at least one
direction, greater than the diameter of the bore 56. The enlargement 92
prevents the needle safety device 44 from sliding off the needle 16 when
the needle tip 18 is received between the first and second jaws 55, 62 as
is shown in FIGS. 4e and 4f.

[0057] As illustrated in FIGS. 4a and 4d, two generally L-shaped
extensions 94 are formed on opposite sides of the needle safety device 44
in the proximal region of the base portion 52 of the main part 46. Each
L-shaped extension 94 has an axial section 96 which extends in the axial
direction at a distance from the base portion 52 of the needle safety
device 44.

[0058] The L-shaped extensions 94 are dimensioned such that proximal end
portions 98 of the proximal tube sections 34 of the introducer hub 14 are
tightly received between the axial section 96 of the L-shaped extensions
and the base portion 52 of the needle safety device 44 when the needle
safety device 44 is received in the chamber 42 defined by the tube
sections 34, 44 of the introducer hub 14 and the needle hub 20, as shown
in FIGS. 1a and 1c.

[0059] In order to retain the proximal tube sections 34 of the introducer
hub 14 in engagement with the L-shaped extensions 94 of the needle safety
device 44, locking grooves 100 are provided in the inner surfaces of the
axial sections 96 of the L-shaped extensions 94 and corresponding locking
protrusions 102 are provided at the outer surfaces of the proximal tube
sections 34 of the introducer hub 14 (FIGS. 1c and 2).

[0060] As is best seen in FIG. 3, the tube sections 40 of the needle hub
20 pass into a tube-like portion 104 of the main body 38 of the needle
hub 20. The tube-like portion 104 is configured to receive not only the
base portion 52 of the needle safety device 44 but also a part of the
proximal tube sections 34 of the introducer hub 14 (FIGS. 1a and 1c).

[0061] In order to secure the proximal tube sections 34 of the introducer
hub 14 in the tube-like portion 104 of the needle hub 20, locking grooves
106 are provided in the inner surface of the tube-like portion 104 of the
needle hub 20 (FIG. 3) and corresponding locking protrusions 108 are
formed at the outer surface of the proximal tube sections 34 of the
introducer hub 14 in a distance distal from the locking protrusions 102
provided for engagement with the needle safety device 44 (FIGS. 1c and
2).

[0062] The engagement of the locking protrusions 108 with the locking
grooves 106 prevent the needle hub 20 from being accidentally released
from the introducer hub 14.

[0063] At the same time, the locking engagement of the locking protrusions
102 with the locking grooves 100 secure the needle safety device 44 at
the introducer hub 14, thereby preventing the needle safety device 44
from being accidentally withdrawn from the introducer hub 14 before the
needle tip 18 has been received between the first and second jaws 55, 62
of the needle safety device 44.

[0065] Similar to the embodiment of FIG. 4 the needle safety device 44
shown in FIG. 5 comprises a main part 46 and a tension ring 50. However,
in contrast to the embodiment of FIG. 4, the needle safety device 44
shown in FIG. 5 does not have any separate clip 48. Instead, the main
part 46 comprises a base portion 52 and two elongate portions 110, 112
that extend from the base portion 52 generally in the axial direction to
fogy in the first and second jaws 55, 62.

[0066] The base portion 52 and the two elongate portions 110, 112 are
integrally formed and made, for example, from a plastic material. The
base portion 52 is of substantially cylindrical shape and has a bore 56
extending therethrough in the axial direction for receiving the needle
16. The bore 56 has a generally circular cross section that is adapted to
the main outer profile of the needle 16.

[0067] The elongate portions 110, 112 each have a proximal section 114 and
a distal section 116. While the proximal sections 114 extend generally
parallel to each other, the distal sections 116 are inclined towards each
other in the collapsed state of the needle safety device 44 (FIGS. 5e and
5f) or when no needle 16 extends through the needle safety device 44
(FIGS. 5a to 5d).

[0068] The distal section 116 of the second jaw 62 passes into a head
section part 84 which extends beyond the free end of the first jaw 55.
The head section part 84 includes an end section 118 which extends in a
radial direction towards the first jaw 55. The length of the end section
118 is such that it covers at least a portion of the free end of the
first jaw 55 when the needle safety device 44 is in its collapsed state
in order to prevent the needle tip 18 from protruding out of the needle
safety device 44 (FIGS. 5e and 5f).

[0069] The tension ring 50 surrounds the first and second jaws 55, 62 in
the region of their distal sections 116. The tension ring 50 is made from
a material having elastic properties, for example rubber. The tension
ring 50 is configured so that the first and second jaws 55, 62 are
deflected against a restoring force of the tension ring 50, when the
needle 16 extends all the way through the needle safety device 44.

[0070] Two generally L-shaped extensions 94 are formed on opposite sides
of the needle safety device 44. The L-shaped extensions 94 emerge from
reinforced portions 120 of the first and second jaws 55, 62 in the
proximal end region of the first and second jaws 55, 62. Each L-shaped
extension 94 has an axial section 96 which extends in the axial direction
at a distance from the respective reinforced portion 120.

[0071] The L-shaped extensions 94 are dimensioned such that proximal end
portions 98 of the proximal tube sections 34 of the introducer hub 14 are
tightly received between the axial sections 96 of the L-shaped extensions
and the reinforced portions 120 of the needle safety device 44 when the
needle safety device 44 is received in the chamber 42 defined by the tube
sections 34, 44 of the introducer hub 14 and the needle hub 20, as shown
in FIGS. 1a and 1c.

[0072] Contrary to the embodiment of FIG. 4, the L-shaped extensions 94 of
the needle safety device 44 shown in FIG. 5 do not have any locking
grooves 100 in the inner surfaces of the axial sections 96 of the
L-shaped extensions 94. Instead, the reinforced portions 120 are provided
with locking shoulders 122 for retaining the proximal tube sections 34 of
the introducer hub 14 between the axial sections 96 of the L-shaped
extensions and the reinforced portions 120 of the needle safety device
44. Accordingly, the proximal tube sections 34 of the introducer hub 14
should be provided with corresponding locking means at their inner
surfaces, for example, suitable depressions.